package org.apache.maven.lifecycle.internal;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

import javax.inject.Inject;
import javax.inject.Named;
import javax.inject.Provider;
import javax.inject.Singleton;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.resolver.filter.ArtifactFilter;
import org.apache.maven.artifact.resolver.filter.CumulativeScopeArtifactFilter;
import org.apache.maven.execution.ExecutionEvent;
import org.apache.maven.execution.MavenSession;
import org.apache.maven.internal.MultilineMessageHelper;
import org.apache.maven.lifecycle.LifecycleExecutionException;
import org.apache.maven.lifecycle.MissingProjectException;
import org.apache.maven.plugin.BuildPluginManager;
import org.apache.maven.plugin.MavenPluginManager;
import org.apache.maven.plugin.MojoExecution;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugin.MojoExecutionRunner;
import org.apache.maven.plugin.MojosExecutionStrategy;
import org.apache.maven.plugin.MojoFailureException;
import org.apache.maven.plugin.PluginConfigurationException;
import org.apache.maven.plugin.PluginIncompatibleException;
import org.apache.maven.plugin.PluginManagerException;
import org.apache.maven.plugin.descriptor.MojoDescriptor;
import org.apache.maven.project.MavenProject;
import org.codehaus.plexus.util.StringUtils;
import org.eclipse.aether.SessionData;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * <p>
 * Executes an individual mojo
 * </p>
 * <strong>NOTE:</strong> This class is not part of any public api and can be changed or deleted without prior notice.
 *
 * @author Jason van Zyl
 * @author Benjamin Bentmann
 * @author Kristian Rosenvold
 * @since 3.0
 */
@Named
@Singleton
public class MojoExecutor
{

    private static final Logger LOGGER = LoggerFactory.getLogger( MojoExecutor.class );

    private final BuildPluginManager pluginManager;
    private final MavenPluginManager mavenPluginManager;
    private final LifecycleDependencyResolver lifeCycleDependencyResolver;
    private final ExecutionEventCatapult eventCatapult;

    private final OwnerReentrantReadWriteLock aggregatorLock = new OwnerReentrantReadWriteLock();

    private final Provider<MojosExecutionStrategy> mojosExecutionStrategy;

    private final Map<Thread, MojoDescriptor> mojos = new ConcurrentHashMap<>();

    @Inject
    public MojoExecutor(
            BuildPluginManager pluginManager,
            MavenPluginManager mavenPluginManager,
            LifecycleDependencyResolver lifeCycleDependencyResolver,
            ExecutionEventCatapult eventCatapult,
            Provider<MojosExecutionStrategy> mojosExecutionStrategy )
    {
        this.pluginManager = pluginManager;
        this.mavenPluginManager = mavenPluginManager;
        this.lifeCycleDependencyResolver = lifeCycleDependencyResolver;
        this.eventCatapult = eventCatapult;
        this.mojosExecutionStrategy = mojosExecutionStrategy;
    }

    public DependencyContext newDependencyContext( MavenSession session, List<MojoExecution> mojoExecutions )
    {
        Set<String> scopesToCollect = new TreeSet<>();
        Set<String> scopesToResolve = new TreeSet<>();

        collectDependencyRequirements( scopesToResolve, scopesToCollect, mojoExecutions );

        return new DependencyContext( session.getCurrentProject(), scopesToCollect, scopesToResolve );
    }

    private void collectDependencyRequirements( Set<String> scopesToResolve, Set<String> scopesToCollect,
                                                Collection<MojoExecution> mojoExecutions )
    {
        for ( MojoExecution mojoExecution : mojoExecutions )
        {
            MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();

            scopesToResolve.addAll( toScopes( mojoDescriptor.getDependencyResolutionRequired() ) );

            scopesToCollect.addAll( toScopes( mojoDescriptor.getDependencyCollectionRequired() ) );
        }
    }

    private Collection<String> toScopes( String classpath )
    {
        Collection<String> scopes = Collections.emptyList();

        if ( StringUtils.isNotEmpty( classpath ) )
        {
            if ( Artifact.SCOPE_COMPILE.equals( classpath ) )
            {
                scopes = Arrays.asList( Artifact.SCOPE_COMPILE, Artifact.SCOPE_SYSTEM, Artifact.SCOPE_PROVIDED );
            }
            else if ( Artifact.SCOPE_RUNTIME.equals( classpath ) )
            {
                scopes = Arrays.asList( Artifact.SCOPE_COMPILE, Artifact.SCOPE_RUNTIME );
            }
            else if ( Artifact.SCOPE_COMPILE_PLUS_RUNTIME.equals( classpath ) )
            {
                scopes = Arrays.asList( Artifact.SCOPE_COMPILE, Artifact.SCOPE_SYSTEM, Artifact.SCOPE_PROVIDED,
                                        Artifact.SCOPE_RUNTIME );
            }
            else if ( Artifact.SCOPE_RUNTIME_PLUS_SYSTEM.equals( classpath ) )
            {
                scopes = Arrays.asList( Artifact.SCOPE_COMPILE, Artifact.SCOPE_SYSTEM, Artifact.SCOPE_RUNTIME );
            }
            else if ( Artifact.SCOPE_TEST.equals( classpath ) )
            {
                scopes = Arrays.asList( Artifact.SCOPE_COMPILE, Artifact.SCOPE_SYSTEM, Artifact.SCOPE_PROVIDED,
                                        Artifact.SCOPE_RUNTIME, Artifact.SCOPE_TEST );
            }
        }
        return Collections.unmodifiableCollection( scopes );
    }

    public void execute( final MavenSession session,
                         final List<MojoExecution> mojoExecutions,
                         final ProjectIndex projectIndex )
        throws LifecycleExecutionException

    {
        final DependencyContext dependencyContext = newDependencyContext( session, mojoExecutions );

        final PhaseRecorder phaseRecorder = new PhaseRecorder( session.getCurrentProject() );

        mojosExecutionStrategy.get().execute( mojoExecutions, session, new MojoExecutionRunner()
        {
            @Override
            public void run( MojoExecution mojoExecution ) throws LifecycleExecutionException
            {
                MojoExecutor.this.execute( session, mojoExecution, projectIndex, dependencyContext, phaseRecorder );
            }
        } );
    }

    private void execute( MavenSession session, MojoExecution mojoExecution, ProjectIndex projectIndex,
                         DependencyContext dependencyContext, PhaseRecorder phaseRecorder )
        throws LifecycleExecutionException
    {
        execute( session, mojoExecution, projectIndex, dependencyContext );
        phaseRecorder.observeExecution( mojoExecution );
    }

    private void execute( MavenSession session, MojoExecution mojoExecution, ProjectIndex projectIndex,
                          DependencyContext dependencyContext )
        throws LifecycleExecutionException
    {
        MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();

        try
        {
            mavenPluginManager.checkRequiredMavenVersion( mojoDescriptor.getPluginDescriptor() );
        }
        catch ( PluginIncompatibleException e )
        {
            throw new LifecycleExecutionException( mojoExecution, session.getCurrentProject(), e );
        }

        if ( mojoDescriptor.isProjectRequired() && !session.getRequest().isProjectPresent() )
        {
            Throwable cause = new MissingProjectException(
                "Goal requires a project to execute" + " but there is no POM in this directory ("
                    + session.getExecutionRootDirectory() + ")."
                    + " Please verify you invoked Maven from the correct directory." );
            throw new LifecycleExecutionException( mojoExecution, null, cause );
        }

        if ( mojoDescriptor.isOnlineRequired() && session.isOffline() )
        {
            if ( MojoExecution.Source.CLI.equals( mojoExecution.getSource() ) )
            {
                Throwable cause = new IllegalStateException(
                    "Goal requires online mode for execution" + " but Maven is currently offline." );
                throw new LifecycleExecutionException( mojoExecution, session.getCurrentProject(), cause );
            }
            else
            {
                eventCatapult.fire( ExecutionEvent.Type.MojoSkipped, session, mojoExecution );

                return;
            }
        }

        doExecute( session, mojoExecution, projectIndex, dependencyContext );
    }

    /**
     * Aggregating mojo executions (possibly) modify all MavenProjects, including those that are currently in use
     * by concurrently running mojo executions. To prevent race conditions, an aggregating execution will block
     * all other executions until finished.
     * We also lock on a given project to forbid a forked lifecycle to be executed concurrently with the project.
     * TODO: ideally, the builder should take care of the ordering in a smarter way
     * TODO: and concurrency issues fixed with MNG-7157
     */
    private class ProjectLock implements AutoCloseable
    {
        final Lock acquiredAggregatorLock;
        final OwnerReentrantLock acquiredProjectLock;

        ProjectLock( MavenSession session, MojoDescriptor mojoDescriptor )
        {
            mojos.put( Thread.currentThread(), mojoDescriptor );
            if ( session.getRequest().getDegreeOfConcurrency() > 1 )
            {
                boolean aggregator = mojoDescriptor.isAggregator();
                acquiredAggregatorLock = aggregator ? aggregatorLock.writeLock() : aggregatorLock.readLock();
                acquiredProjectLock = getProjectLock( session );
                if ( !acquiredAggregatorLock.tryLock() )
                {
                    Thread owner = aggregatorLock.getOwner();
                    MojoDescriptor ownerMojo = owner != null ? mojos.get( owner ) : null;
                    String str = ownerMojo != null ? " The " + ownerMojo.getId() : "An";
                    String msg = str + " aggregator mojo is already being executed "
                            + "in this parallel build, those kind of mojos require exclusive access to "
                            + "reactor to prevent race conditions. This mojo execution will be blocked "
                            + "until the aggregator mojo is done.";
                    warn( msg );
                    acquiredAggregatorLock.lock();
                }
                if ( !acquiredProjectLock.tryLock() )
                {
                    Thread owner = acquiredProjectLock.getOwner();
                    MojoDescriptor ownerMojo = owner != null ? mojos.get( owner ) : null;
                    String str = ownerMojo != null ? " The " + ownerMojo.getId() : "A";
                    String msg = str + " mojo is already being executed "
                            + "on the project " + session.getCurrentProject().getGroupId()
                            + ":" + session.getCurrentProject().getArtifactId() + ". "
                            + "This mojo execution will be blocked "
                            + "until the mojo is done.";
                    warn( msg );
                    acquiredProjectLock.lock();
                }
            }
            else
            {
                acquiredAggregatorLock = null;
                acquiredProjectLock = null;
            }
        }

        @Override
        public void close()
        {
            // release the lock in the reverse order of the acquisition
            if ( acquiredProjectLock != null )
            {
                acquiredProjectLock.unlock();
            }
            if ( acquiredAggregatorLock != null )
            {
                acquiredAggregatorLock.unlock();
            }
            mojos.remove( Thread.currentThread() );
        }

        @SuppressWarnings( { "unchecked", "rawtypes" } )
        private OwnerReentrantLock getProjectLock( MavenSession session )
        {
            SessionData data = session.getRepositorySession().getData();
            // TODO: when resolver 1.7.3 is released, the code below should be changed to
            // TODO: Map<MavenProject, Lock> locks = ( Map ) ((Map) data).computeIfAbsent(
            // TODO:         ProjectLock.class, l -> new ConcurrentHashMap<>() );
            Map<MavenProject, OwnerReentrantLock> locks = ( Map ) data.get( ProjectLock.class );
            // initialize the value if not already done (in case of a concurrent access) to the method
            if ( locks == null )
            {
                // the call to data.set(k, null, v) is effectively a call to data.putIfAbsent(k, v)
                data.set( ProjectLock.class, null, new ConcurrentHashMap<>() );
                locks = ( Map ) data.get( ProjectLock.class );
            }
            return locks.computeIfAbsent( session.getCurrentProject(), p -> new OwnerReentrantLock() );
        }
    }

    static class OwnerReentrantLock extends ReentrantLock
    {
        @Override
        public Thread getOwner()
        {
            return super.getOwner();
        }
    }

    static class OwnerReentrantReadWriteLock extends ReentrantReadWriteLock
    {
        @Override
        public Thread getOwner()
        {
            return super.getOwner();
        }
    }

    private static void warn( String msg )
    {
        for ( String s : MultilineMessageHelper.format( msg ) )
        {
            LOGGER.warn( s );
        }
    }

    private void doExecute( MavenSession session, MojoExecution mojoExecution, ProjectIndex projectIndex,
                            DependencyContext dependencyContext )
            throws LifecycleExecutionException
    {
        MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();

        List<MavenProject> forkedProjects = executeForkedExecutions( mojoExecution, session, projectIndex );

        ensureDependenciesAreResolved( mojoDescriptor, session, dependencyContext );

        try ( ProjectLock lock = new ProjectLock( session, mojoDescriptor ) )
        {
            doExecute2( session, mojoExecution );
        }
        finally
        {
            for ( MavenProject forkedProject : forkedProjects )
            {
                forkedProject.setExecutionProject( null );
            }
        }
    }

    private void doExecute2( MavenSession session, MojoExecution mojoExecution )
            throws LifecycleExecutionException
    {
        eventCatapult.fire( ExecutionEvent.Type.MojoStarted, session, mojoExecution );
        try
        {
            try
            {
                pluginManager.executeMojo( session, mojoExecution );
            }
            catch ( MojoFailureException | PluginManagerException | PluginConfigurationException
                | MojoExecutionException e )
            {
                throw new LifecycleExecutionException( mojoExecution, session.getCurrentProject(), e );
            }

            eventCatapult.fire( ExecutionEvent.Type.MojoSucceeded, session, mojoExecution );
        }
        catch ( LifecycleExecutionException e )
        {
            eventCatapult.fire( ExecutionEvent.Type.MojoFailed, session, mojoExecution, e );

            throw e;
        }
    }

    public void ensureDependenciesAreResolved( MojoDescriptor mojoDescriptor, MavenSession session,
                                               DependencyContext dependencyContext )
        throws LifecycleExecutionException

    {
        MavenProject project = dependencyContext.getProject();
        boolean aggregating = mojoDescriptor.isAggregator();

        if ( dependencyContext.isResolutionRequiredForCurrentProject() )
        {
            Collection<String> scopesToCollect = dependencyContext.getScopesToCollectForCurrentProject();
            Collection<String> scopesToResolve = dependencyContext.getScopesToResolveForCurrentProject();

            lifeCycleDependencyResolver.resolveProjectDependencies( project, scopesToCollect, scopesToResolve, session,
                                                                    aggregating, Collections.emptySet() );

            dependencyContext.synchronizeWithProjectState();
        }

        if ( aggregating )
        {
            Collection<String> scopesToCollect = toScopes( mojoDescriptor.getDependencyCollectionRequired() );
            Collection<String> scopesToResolve = toScopes( mojoDescriptor.getDependencyResolutionRequired() );

            if ( dependencyContext.isResolutionRequiredForAggregatedProjects( scopesToCollect, scopesToResolve ) )
            {
                for ( MavenProject aggregatedProject : session.getProjects() )
                {
                    if ( aggregatedProject != project )
                    {
                        lifeCycleDependencyResolver.resolveProjectDependencies( aggregatedProject, scopesToCollect,
                                                                                scopesToResolve, session, aggregating,
                                                                                Collections.emptySet() );
                    }
                }
            }
        }

        ArtifactFilter artifactFilter = getArtifactFilter( mojoDescriptor );
        List<MavenProject> projectsToResolve =
            LifecycleDependencyResolver.getProjects( session.getCurrentProject(), session,
                                                     mojoDescriptor.isAggregator() );
        for ( MavenProject projectToResolve : projectsToResolve )
        {
            projectToResolve.setArtifactFilter( artifactFilter );
        }
    }

    private ArtifactFilter getArtifactFilter( MojoDescriptor mojoDescriptor )
    {
        String scopeToResolve = mojoDescriptor.getDependencyResolutionRequired();
        String scopeToCollect = mojoDescriptor.getDependencyCollectionRequired();

        List<String> scopes = new ArrayList<>( 2 );
        if ( StringUtils.isNotEmpty( scopeToCollect ) )
        {
            scopes.add( scopeToCollect );
        }
        if ( StringUtils.isNotEmpty( scopeToResolve ) )
        {
            scopes.add( scopeToResolve );
        }

        if ( scopes.isEmpty() )
        {
            return null;
        }
        else
        {
            return new CumulativeScopeArtifactFilter( scopes );
        }
    }

    public List<MavenProject> executeForkedExecutions( MojoExecution mojoExecution, MavenSession session,
                                                       ProjectIndex projectIndex )
        throws LifecycleExecutionException
    {
        List<MavenProject> forkedProjects = Collections.emptyList();

        Map<String, List<MojoExecution>> forkedExecutions = mojoExecution.getForkedExecutions();

        if ( !forkedExecutions.isEmpty() )
        {
            eventCatapult.fire( ExecutionEvent.Type.ForkStarted, session, mojoExecution );

            MavenProject project = session.getCurrentProject();

            forkedProjects = new ArrayList<>( forkedExecutions.size() );

            try
            {
                for ( Map.Entry<String, List<MojoExecution>> fork : forkedExecutions.entrySet() )
                {
                    String projectId = fork.getKey();

                    int index = projectIndex.getIndices().get( projectId );

                    MavenProject forkedProject = projectIndex.getProjects().get( projectId );

                    forkedProjects.add( forkedProject );

                    MavenProject executedProject = forkedProject.clone();

                    forkedProject.setExecutionProject( executedProject );

                    List<MojoExecution> mojoExecutions = fork.getValue();

                    if ( mojoExecutions.isEmpty() )
                    {
                        continue;
                    }

                    try
                    {
                        session.setCurrentProject( executedProject );
                        session.getProjects().set( index, executedProject );
                        projectIndex.getProjects().put( projectId, executedProject );

                        eventCatapult.fire( ExecutionEvent.Type.ForkedProjectStarted, session, mojoExecution );

                        execute( session, mojoExecutions, projectIndex );

                        eventCatapult.fire( ExecutionEvent.Type.ForkedProjectSucceeded, session, mojoExecution );
                    }
                    catch ( LifecycleExecutionException e )
                    {
                        eventCatapult.fire( ExecutionEvent.Type.ForkedProjectFailed, session, mojoExecution, e );

                        throw e;
                    }
                    finally
                    {
                        projectIndex.getProjects().put( projectId, forkedProject );
                        session.getProjects().set( index, forkedProject );
                        session.setCurrentProject( project );
                    }
                }

                eventCatapult.fire( ExecutionEvent.Type.ForkSucceeded, session, mojoExecution );
            }
            catch ( LifecycleExecutionException e )
            {
                eventCatapult.fire( ExecutionEvent.Type.ForkFailed, session, mojoExecution, e );

                throw e;
            }
        }

        return forkedProjects;
    }
}
